Gija Joseon was a dynasty of Gojoseon allegedly founded by the sage Jizi (Gija), a member of the Shang dynasty royal house. Concrete evidence for Jizi's role in the history of Gojoseon is lacking, and the narrative has been challenged since the 20th century.
Gija
Gojoseon, also called Joseon, was the first kingdom on the Korean Peninsula. According to Korean mythology, the kingdom was established by the legendary king Dangun. Gojoseon possessed the most advanced culture in the Korean Peninsula at the time and was an important marker in the progression towards the more centralized states of later periods. The addition of Go, meaning "ancient", is used in historiography to distinguish the kingdom from the Joseon dynasty, founded in 1392 CE.
Heaven Lake of Baekdu Mountain, where Dangun's father is said to have descended from heaven